The use of the screening technique as a method of rapidly estimating vaccine efficacy

Using measles notification data for the period December 1st, 1987 to May 31st, 1988, in Leeds, an estimation of measles vaccine efficacy is calculated using the screening technique. This is an equation which allows the rapid estimation of vaccine efficacy and is useful in an outbreak situation in deciding whether the proportion of cases with a vaccination history is still compatible with a good overall vaccine efficacy. No vaccine is 100% effective and the screening technique, which uses readily available data, will quickly indicate whether a more detailed epidemiological investigation is required into vaccine failure.